Such heating ceilings are mostly known in connection with rearing small animals. In rearing e.g. pigs it is common to use additional heat over certain portions of the room areas where the animals are kept. This is desirable since a piglet a few weeks old gives off considerable amounts of heat and since the temperature in the shed is kept low in relation to the temperature of the piglet for reasons of heat economy and with regard to the well-being of the sow.
The additional heat has so far been obtained either from heat lamps or ceiling units with a heat producing surface. The known heat emitting devices are continuous heat generators being raisable and lowerable to control the mount of emitted energy per surface unit.